1. By EPS Pre expander Machine heating, the EPS beads are expanded, and the volume is increased to make a corresponding change in density (for example, from 620 g / liter (bulk density, true density: 1000 g / liter) decrease to 15 g / liter – 100 g /L) ,to achieve the density we need.

– the magnitude of the change depends on the temperature of the heated steam and the time of heating.

2. The vapor condenses in the EPS beads, releasing heat to soften the EPS and expanding the blowing agent in the EPS beads, thereby expanding the EPS beads.